The samurai had the same situation going in the 14 hundred and 15 hundred, for example. Ther hundreds of thousands of these guys, and they fought a lot. Japan is in the process of some very big wars that will lead up to a big battle,. famous the saci gahara battle in 16 hundred. When one side beat the other, it it was the big push over. Capsize moment when japan kind of gets unified.
The Asia-Pacific War of 1937-1945 has deep roots. It also involves a Japanese society that's been called one of the most distinctive on Earth. If there were a Japanese version of Captain America, this would be his origin story.